A platform used in agriculture harvesting crops is universally defined as a header attached to a harvesting machine and that serves as a removable attachment for use when cutting requirements are requested. It is made and assembled onto a main frame which is divided into a central section, the area corresponding to coupling with the harvester, and two side sections wings, that projects on either side of said central section according to a perpendicular direction to the advance direction of the harvesting machine. The platform has a cutting mechanism cutterbar projecting laterally across the width thereof, defined in front of the side sections and center section, and is configured to sever the standing crop.
Platforms contain a system for the transverse movement of the crop material. Typically it is formed by a helical screw conveyor and alternately today there exist systems containing a set of canvas or drapers for conveying. Both the canvas draper and the screw conveyor operate to transport the crop cut by the cutterbar and drive it into the center section. Furthermore, it is well known there are multitudes of arrangements where gadgets are used to force the material that reaches the center section of platform to pass through an open end and to the combine's feeder thereof, to be later threshed by the harvester. Each header prefer one of these devices and determine the input mode of the crop material to the feeder of the combine tractor.
It is known that the cutterbar of some cutting platform is configured to flex in response to ground shape. In these, a series of sliding plates skid shoes are linked to said cutterbar to confer the ability to settle above the ground and slipping while operating. All this in view of making the cut of the plant as close to the ground as possible in practice, allowing the collection of those pods with beans sprouting in the lower part of the stem. Thus, when the head is advanced in work, the cutterbar is positioned virtually glued to the ground and curling up to mimic the natural unevenness of the field, resulting into a crop cut at constant height.
Traditional platforms be it platforms using configurations according to prior art technologies implemented for cutting crops such as soybeans, wheat, barley, safflower or beans (among others) usually comprise a conveyor belt on each lateral section which projects forward from the main frame in an oblique downward direction, describing a driving surface for the crop material that extends to the cutterbar, without interruption.
During grain harvesting operations, there is typically a significant amount of crop residue that must be controlled at the platform. If the residue is allowed to migrate into the interior of the draper assemblies, it can become lodged in critical areas and interfere with movement of the draper belts. The problem starts in the transition region between the cutterbar assembly and the front edges of the draper assemblies because the endless loop in the belts present exposed openings to the interior of the belts in that area.
While prior art mechanism use interlocked belt guards in the transition region to cover the open front of the draper belt assemblies against ingress of crop material, it is a challenge to effectively mimic the curved shape of the cutterbar to perfectly seal off the area, particularly considering that the cutterbar assembly and draper assemblies are flexing up and down at various locations.
Other drawback with the crop dam used in flexible cutterbars is the existence of protuberances like bolt ends and nuts that worsen the crop flow. Most prior art crop dam designs are focused to create a good sealing to the draper conveyor while they leave uncovered the fastening item used. In crops like soybean or butter-bean, lower pods tend to be scratched by this protuberances and in severe conditions they open up and release the grains to the floor.